Battery Watering System Tubing Connector

ABSTRACT

A battery watering system for delivering fluid to a battery has a connection to a fluid source, which is to be delivered to a plurality of battery filling valve assemblies mounted to a plurality of battery filling openings on a battery. Tubing sections are used to interconnect the fluid source to the battery filling valve assemblies. Each battery filling valve assembly has a connector for receiving at least one tube end in at least one tubing receiving aperture having an inner diameter sized to receive the tubing end therein, at least one inner diameter reducing projection disposed within the aperture for applying a restraining force on the tube end disposed therein to limit withdrawal therefrom. Using the inventive connectors, rapid assembly with sure connection of the tubing sections is assured and inadvertent disconnection substantially avoided.

CROSS REFERENCE TO RELATED APPLICATIONS

This invention claims priority in U.S. Provisional patent application no. 60/719,399, filed Sep. 22, 2005.

TECHNICAL FIELD

The invention relates to tubing connectors, in particular, to tubing connectors for use on single point battery watering or refilling devices, for example, as installed on rechargeable batteries.

BACKGROUND

Single point battery watering has become the method of choice for replenishing the fluids lost during use of rechargeable batteries. For example, lead-acid batteries require the periodic addition of water, to make up for water lost through evaporation and gassing.

It has been standard practice to run a water conduit, for example, a flexible plastic tubing from a supply point to a first single point battery watering device and to connect this first device to a second via a continuation of the conduit, and so on, so as to provide a substantially series connected feed to the single point battery watering devices located on a battery.

The series connected feed can, optionally, be branched, whereby at least two series connected feeds are effectively run in parallel, receiving water via a single supply conduit connected to the supply point.

The conduit is preferably divided into sections consisting of individual lengths of plastic tubing that provide fluid links between successive single point battery watering devices.

Attachment of the ends of the individual lengths of tubing to their associated single point battery watering devices has typically been achieved by having protruding tubular stub connectors on the single point battery watering devices adapted to accept the ends of the individual lengths of tubing slid thereon.

In this arrangement, the inner diameter of the individual lengths of tubing would typically be marginally less than the outer diameter of the tubular stub connectors, causing the ends of the individual lengths of tubing to be expanded and thereby to provide sufficient friction in an interference fit to keep the tubing attached to the stub connectors.

While a comparatively smooth outer face on the stub connectors can easily maintain a hold on the end of the tubing and thereby also maintain an effective seal at a low water supply pressure, for example, equivalent to a supply head less that 2 meters, at higher supply pressure, for example, equivalent to 10 meters or greater, a smooth face might generally prove inadequate to the task of maintaining a hold and a seal, thus requiring the stub connector to be adapted to include one or more outwardly protruding circular barbs. These typically permit the ends of the tubing to slide on, yet thereafter provide a significantly greater hold on the ends of the tubing.

Generally, plastic tubing has a tendency to adapt to a new shape, as provided by the barbs and consequently, the grip of the tubing on the barbed stub connectors will inevitably diminish over time. This has the effect of eventually causing the tubing to expand and slide off the barbs upon application of even a comparatively low water supply pressure, resulting in inadvertent disconnection.

To prevent this inadvertent disconnection, it has been common practice to include ferrules or tubular rings over the ends of the tubing, for exerting a compressive force on the outside of the plastic tubing, so that it remains tightly engaged with the barbs, at least for as long as the ferrules remain intact.

A major disadvantage in the use of ferrules is the labor involved in the fitting of the ferrules, which is likely to increase the time for installation of the single point battery watering devices by a factor of two or more.

Another disadvantage in the use of ferrules is that they require great care by the installer, as the installer must take care to avoid even a single inadvertent disconnection in an entire system, which is the equivalent of breaking a single link in a chain, as the result is the entire system must shut down.

Another approach that has been used is to employ tubular stub connectors having an inner diameter sufficiently large to receive therein the outer diameter of the tubing and by way of threading, to run a single length of tubing via multiple, series connected tubular stub connectors, substantially from the supply point all the way to the last single point watering cap in a series connected string. In this arrangement, the water is permitted to exit the tubing and to enter individual single point battery watering caps via special perforations made in the tubing. Sealing is achieved via an O-ring provided within the tubular stub connectors.

In this arrangement it is important that the tubing be able to be passed through a succession of tubular stub connectors sufficiently easily to facilitate installation, yet to be secured sufficiently fast to ensure the tubing remains in place afterwards, clearly contradictory requirements. In practice, the tubing has been found to move relatively easily with respect to the individual tubular stub connectors after completion of the installation and during normal operation of the system, thereby exposing the perforations of the tubing and resulting in a system breakdown.

The location of the single point battery watering devices on the top of lead acid batteries can be hazardous to the tubing. A battery may weigh as much as 5000 kilograms and can possess considerable inertia when being moved, for example into or out of a vehicle. Thus, the exposed tubing can become ensnared with surrounding objects, causing the tubing to be pulled free from the connectors, again resulting in a system breakdown.

SUMMARY OF THE PRESENT INVENTION

It is an object of the present invention to overcome the above described disadvantages by providing a battery watering system tubing connector which provides a hooking tubing connection or fastening arrangement which applies increasing sealing pressure, and increasing restraining pressure, to the tubing in response to increasing fluid supply pressure, while at the same time being capable of retain a minimum sealing and restraining pressure at a zero fluid supply pressure. The invention further comprises using the battery watering system tubing connector with an apparatus for conveying a filling fluid across an upper wall of a receiving vessel containing therein energy storage elements, for example, for conveying battery replenishment water, across the lids of acid or alkali containing battery cells, each cell equipped with a number of positive and negative electrodes and separator elements therein, the connecting or fastening arrangement imparting a direction bias to the tubing runs or portions sufficient to enable the tubing to be curved in the direction of the receiving vessel.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is described relative to the following drawings where

FIG. 1 shows a sectional schematic representation of a battery filling device with a tubing connector of the invention located on a battery cell;

FIG. 2 shows a partial sectional representation of a tubing connector of the invention and an end of a length of tubing about to be inserted into the tubing connector; and,

FIG. 3 shows a sectional schematic representation of a battery assembly, including battery filling devices and interconnecting tubing.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a single point battery filling device or a battery filling valve assembly 10 located on a battery cell 54 and arranged to receive battery filling fluid from a suitable source generally as described in U.S. Pat. Nos. 4,359,071, 6,427,732, 6,635,387 and 6,675,842. Optionally, the filling fluid may be provided from a suitable reservoir or from a pressure reducing valve tied into a supply header. There are many ways in which a filling fluid may be provided as the source for the assembly 10. Also, there are various fluids that can be used as the filling fluids, for example, this may comprise purified water, treated water, battery electrolyte or combinations thereof.

Conduit portions are formed by a tee connector 12 and tubing sections 22 and 24. The assembly 10 and the battery cell 54 correspond generally to a portion of a typical battery equipped with a battery filling system, as described for example in U.S. Pat. No. 6,427,732. The assembly 10 is operated generally in cooperation with a filler unit designed for topping up a container with liquid, for example as described in U.S. Pat. No. 4,544,004. In such a unit, filling fluid, typically water is supplied to the assembly 10 under pressure and it exists under pressure within the conduit portions formed by the tee connector 12 and tubing sections 22 and 24. The water is flowable via a duct 32, past a valve seat 38, over a valve 40 and over a float 42 into a cup-like base vessel 36, hence via an orifice 44 and a level sensing tube 46 and an associated open end 48, into a battery cell enclosure 56, thereby combining the water with an electrolyte 64 so as to raise the electrolyte level in the battery from a first level 66 to a second level 68. Raising the level of the electrolyte 64 causes the open end 48 to become submerged in the electrolyte 64, raising the pressure within the level sensing tube 46 so as to cause an accumulation of water to occur within the base vessel 36, raising the float 42 to enable the valve 40 to move towards the valve seat 38 and upon the electrolyte attaining the second level 68, which corresponds to a required filling level, the valve 40 sealingly engages the valve seat 38, to halt fluid flow into the battery cell enclosure 56.

Housed within the cell enclosure 56 are a number of positive electrodes or plates 58, a number of negative electrodes or plates 60, which plates are maintained a given distance apart by a number of separator plates 62. The positive plates 58 are electrically connected to a positive (+) terminal 70 and the negative plates are electrically connected to a negative (−) terminal 72. When the battery cell 54 is in a charged condition, a potential, for example, of about 2 volts, is developed across the terminals 70 and 72.

When an overcharge occurs, for example when the potential across the terminals 70 and 72 is raised by external means, so as to exceed approximately 2.4 volts but generally not exceeding 2.8 volts so as to prevent any damage to the battery cell 54, certain gases will be generated within the battery cell enclosure 54, which gases are able to pass out of the cell enclosure 56 via a breather pipe arrangement 50, and via a breather slot arrangement 52.

A covering lid is attached to the base vessel 36 by attaching means, not shown, as these are conventional, and due to the sectional and schematic nature of FIG. 1.

The base vessel 36 may be attached to the cell enclosure 56 by a releasable screw or push-fit plug arrangement, generally in accordance with conventional battery vent caps or plugs.

The tee connector 12 is attached to the covering lid 34 via a plug section 26 and a socket section 28 and is maintained in position by an o-ring 30 which can be made, for example, of rubber, a rubber-like material, or any other suitable material which can be a thermosetting or thermoplastic material. The tee connector 12 is also releasable when sufficient force is applied, and generally, it is designed to be much easier for the tee connector to be attached to the covering lid 34 than it is for it to be released.

Referring to FIGS. 1 and 2, the tee connector 12 has at least one circular tubing receiving aperture 16 and at least one complementary circular tubing receiving aperture 14. In total, the tee connector 12 may include up to five receiving apertures generally corresponding to the receiving apertures 16 and 14 and disposed, for example, spaced at equal angles relative to each other.

The receiving apertures 16 and 14 include an inner diameter reducing projection 20 and an inner diameter reducing projection 18, respectively. The projections 20 and 18 are adapted to apply an inward acting pressure or a constrictive force on the body of the tubing disposed therein, generally as shown in FIGS. 1 and 3, for example, on the tubing sections 24 and 22, respectively, causing the tubing sections 24 and 22 to be reduced in overall diameter at the corresponding locations.

Accordingly, the material of the projections 20 and 18 needs to have a hardness or Durometer rating corresponding to about Shore D 55 or Rockwell R 90, or harder, preferably Shore D 72 or Rockwell R 90, or harder and most preferably Rockwell R 110 or harder. In order to obtain a secure attachment, the tubing material of sections 22 and 24 should have a hardness or Durometer rating corresponding to about Shore D 50 or Shore A 100, or softer, preferably Shore D 24 or Shore A 80, or softer and most preferably Shore A 70, or softer, and perhaps optimally, although not exclusively, Shore A 65.

Referring to FIGS. 1 and 2, the inner diameter reducing projections 20 and 18 includes structures for assisting in the insertion of the tubing sections 24 and 22 respectively, as well as for resisting withdrawal of the of the tubing sections 24 and 22 respectively, for example, as shown in FIG. 2 in respect of the inner diameter reducing projection 20. Thus, by way of example, insertion of the tubing section 24 is assisted by a relatively shallow angle conical guide section 76 and withdrawal arrested by a steep angled, preferably right angled abutment or flange 78, whereby the faces of the guide section 76 and the flange 78 intersect at an angle sufficiently sharp to help prevent withdrawal of the tubing section 24 from the tee connector 12.

Furthermore, the extent of compression or constriction, as imposed by the inner diameter reducing projections 20 and 18 on the outer diameter of the tubing sections 24 and 22, respectively, in relation to the original diameter, is preferably, although not exclusively, between 98% in respect of very hard tubing and 50% in respect of very soft tubing, more preferably between 92% and 70%, and most preferably between 86% and 81%, and ideally 84%, for example, for a good quality PVC tube having a Shore hardness of 65, an outer diameter of 11.11 millimeters and an inner diameter of 6.35 millimeters.

Insertion of the tubing section 24 is typically achieved, by way of example, by a bringing together in the direction of arrow 84 the tubing section 24 and the tee connector 12, and while pressing these together, applying a rotational force or movement 82 to the tubing length 24 with one hand and holding steady the tee connector 12 in the other hand. In this regard, an outer diameter 80 of the tubing length 24 is chosen to provide what may be commonly termed, a snug or slight interference fit within an inner diameter 74 of the tee connector 12. This still allows the process of insertion to proceed fairly easily, while exerting some force to resist withdrawal. The depth of insertion may be limited by a suitable rim or stop, placed within the inner diameter 74, but not shown to ease illustration.

After complete insertion, an application of even a considerable pulling force will not separate the connector and tube section, as compared to the ease of bringing together the tubing section 24 and the tee connector 12. Generally, the force required to separate these, by grasping the tubing section 24 with one hand and the tee connector 12 with the other hand, and pulling apart, would be in excess, for example, of about 15 kilograms, at a temperature of 20° C. in respect of a tubing section 24 made of PVC tubing. When pressurized by the pressure of a filling fluid delivered under pressure, the tubing section 24 will attempt to expand within the confines of the inner diameter reducing projection 20, thereby improving retention with the increasing pressure, so as to further resist separation, as well as improving the sealing between the tubing section 24 and the tee connector 12.

The tee connector 12 has receiving apertures 16 and 14 which project downwardly towards the battery cell 54, to assist in imparting a corresponding curvature into the tubing sections 24 and 22. With reference to FIG. 3, this is shown as providing a series of tubing downwardly curved troughs made up of the tubing sections 24 and 24A, thereby assisting in avoiding snagging by nearby objects when the battery is moved. Furthermore, the troughs are able to retain portions of the applied filling fluid, to restrict an inadvertent passage of a gas between filler assemblies, such as between 10, 10A and 10B.

With reference to FIG. 3, there is shown a portion of a battery, generally in line with motive power or traction batteries, including three battery cells 54, 54A and 54B, each equipped with a single point battering filling device or batter filling valve assembly, 10, 10A and 10B, respectively. In operation, while all three assemblies 10, 10A and 10B are provided with, for example, filling water via a conduit formed by tubing section 22, tee connector 12A, tubing length 24A, tee connector 12B and tubing section 24B, from either a source connection 94 or an alternate source connection 96, each individual assembly 10, 10A and 10B is able to control the flow of filling water into their associated battery cell, 54, 54A and 54B independently, to raise their respective electrolytes 64, 64A and 64B from approximately low levels 66, 66A and 66B to filled levels 68, 68A and 68B, respectively.

The portion of the battery made up of the battery cells 54, 54A and 54B had the individual cells connected electrically in series providing a connection 86, connected to the negative terminal 72; intercell connector 88 which connects the positive terminal 70 to a negative terminal 72A; intercell connector 90 which connects a positive terminal 70A to a negative terminal 72B; and connection 92, connected to a negative terminal 70B; in respect of the cells 10, 10A and 10B, providing thereby a sum of the voltages, for example 2 volts per cell, totaling 6 volts across connections 86 and 92. The direction of the general flow of water via the conduit preferably corresponds to the cell to cell potential gradient, or runs in parallel with the potential gradient of the battery, by way of example, although this may be achieved by feeding from one end or an intermediate connection point. When convenient, an exception can be made to simplify installation, by cross connecting or alternating, yet keeping a potential difference between successive fluid connected assemblies, for example, assemblies 10, 10A and 10B below a specific value, by way of example, below 12 volts.

There are various materials suitable for the construction of the tee connector 12, for example but not exclusively, polystyrene, styrene acrylonitrile, acrylonitrile styrene butadiene co-polymer, methyl methacrylate and similar comparatively rigid plastics. These plastics can be made even more rigid by the addition of a filler, such as by way of a glass filler, among others. A material such as polypropylene might prove too flexible at the inner diameter reducing projections 20 and 18, in this regard.

There are also various materials suitable for the construction of the tubing sections 24 and 22, as well as 24A and 24B, for example but not exclusively, polyvinyl chloride commonly known as PVC, containing a plasticizer that is not readily affected by heat and sulfuric acid, polyethylene—although preferably not a very low density variety, polypropylene, polypropylene-polyethylene co-polymer, polypropylene with a suspended rubber, for example, PP/EPDM, neoprene as well as other suitable rubbers, thermoset and thermoplastic elastomers.

Using the inventive connectors, rapid assembly with sure connection of the tubing sections is assured and inadvertent disconnection substantially avoided. The tube ends are easily assembled to the connectors, and significant force would be required to cause an inadvertent disconnection, thus the time for assembly is reduced, and downtime caused by system failures substantially eliminated.

It will be understood by those skilled in the art that various changes and modifications can be made without meaningfully departing from the spirit and scope of the present invention. 

1. A connector for flexible tubing comprising at least one tubing receiving aperture having an inner diameter sized to receive a tubing end therein, at least one inner diameter reducing projection disposed within the aperture for applying a restraining force on the tube end disposed therein.
 2. The connector of claim 1 further comprising a second inner diameter reducing projection disposed in a facing relationship relative to the at least one inner diameter reducing projection.
 3. The connector of claim 1 where in the connector has two or more tubing receiving apertures.
 4. The connector of claim 1 wherein the connector has from two to four tubing receiving apertures.
 5. The connector of claim 1 further comprising an outlet passage.
 6. The connector of claim 1 wherein the at least one inner diameter reducing projection is composed of a material that is hard, having a hardness of at least about Shore D 55 or Rockwell R
 50. 7. The connector of claim 1 wherein the at least one inner diameter reducing projection is composed of a material that is hard, having a hardness of about Shore D 72 or Rockwell R
 90. 8. The connector of claim 1 wherein the at least one inner diameter reducing projection is composed of a material that is hard, having a hardness of about Rockwell R110.
 9. The connector of claim 1 further comprising a tube receiving guide having a sloped surface, sloped inwardly from an entrance end of the aperture, and having an end for engaging a tubing end disposed within the aperture, the sloped surface easing entry by the tubing end into the aperture, the end engaged to the tubing end to limit withdrawal therefrom.
 10. The connector of claim 1 wherein the connector has two substantially coaxial apertures, a central outlet passage oriented perpendicular to the apertures, each apertures sloped downwardly in a direction leading away from the central outlet passage.
 11. A battery watering system for delivering fluid to a battery comprising; a fluid source; a plurality of battery filling valve assemblies for mounting to a plurality of battery filling openings on the battery; tubing sections for interconnecting the fluid source to the battery filling valve assemblies; each battery filling valve assembly having a connector for receiving at least one tube end in at least one tubing receiving aperture having an inner diameter sized to receive the tubing end therein, at least one inner diameter reducing projection disposed within the aperture for applying a restraining force on the tube end disposed therein to limit withdrawal therefrom.
 12. The battery watering system of claim 11 further comprising a second inner diameter reducing projection disposed in a facing relationship relative to the at least one inner diameter reducing projection.
 13. The battery watering system of claim 11 wherein the connector has two or more tubing receiving apertures.
 14. The battery watering system of claim 11 wherein the connector has from two to four tubing receiving apertures.
 15. The battery watering system of claim 11 wherein the connector has an outlet passage leading to the battery filling valve assemblies.
 16. The battery watering system of claim 11 wherein the connector has a tube receiving guide having a sloped surface, sloped inwardly from an entrance end of the aperture, and having an end for engaging a tubing end disposed within the aperture, the sloped surface easing entry by the tubing end into the aperture, the end engaged to the tubing end to limit withdrawal therefrom.
 17. The battery watering system of claim 11 wherein the connector has two substantially coaxial apertures, a central outlet passage oriented perpendicular to the apertures, each aperture sloped downwardly in a direction leading away from the central outlet passage.
 18. A manifold for adding fluid to a battery having multiple fill ports comprising: a plurality of battery filling valve assemblies, interconnected by a plurality of flexible tubing portions, each battery filling valve assembly having a connector for receiving at least one tube end in at least one tubing receiving aperture, the tubing receiving aperture having an inner diameter sized to receive the tubing end therein, at least one inner diameter reducing projection disposed within the aperture for applying a restraining force on the tube end disposed therein.
 19. The manifold of claim 18 further comprising a second inner diameter reducing projection disposed in a facing relationship relative to the at least one inner diameter reducing projection.
 20. The manifold of claim 18 wherein the connector has 2 or more tubing receiving apertures.
 21. The manifold of claim 18 wherein the connector has an outlet passage leading to the battery filling valve assembly.
 22. The manifold of claim 18 wherein the at least one inner diameter reducing projection is composed of a material that is hard, having a hardness of at least about Shore D 55 or Rockwell R
 50. 23. The manifold of claim 18 wherein the at least one inner diameter reducing projection is composed of a material that is hard, having a hardness of about Shore D 72 or Rockwell R
 90. 24. The manifold of claim 18 wherein the at least one inner diameter reducing projection is composed of a material that is hard, having a hardness of about Rockwell R110.
 25. The manifold of claim 18 wherein the connector has a tube receiving guide having a sloped surface, sloped inwardly from an entrance end of the aperture, and having an end for engaging a tubing end disposed within the aperture, the sloped surface easing entry by the tubing end into the aperture, the end engaged to the tubing end to limit withdrawal therefrom.
 26. The manifold of claim 18 wherein the connector has two substantially coaxial apertures, a central outlet passage oriented perpendicular to the apertures, each aperture sloped downwardly in a direction leading away from the central outlet passage. 